RADAR QUESTION PAPERS

Tuesday, October 13, 2009

respected reader, given below are four question papers of RADAR ENGINEERING, an ELECTIVE subject in B.E. (7th SEM.)( REV.) course, BRANCH(ELECTRONICS AND TELECOMMUNICATION) of MUMBAI UNIVERSITY.

MAY 2009 QUESTION PAPERN.B. (1.)QUESTION NO.1 IS COMPULSORY. (Total Marks:100)(2.) Attempt any four questions out of remaining six questions.(3.) Figures to the right indicate full marks.

1(a.) Explain in brief the various system losses in the radar. (5M)(b.) Compare analog MTI system with digital MTI system. (5M)(c.)Explain doppler shift and its role in pulsed and CW RADAR.(5M)(d.) Explain frequency agility and diversity techniques. (5M).

2 (a.) Derive the simplified version of radar range equation in terms of minimum detectable signal to noise ratio(S/N)min. also explain why (S/N)min. is a better measure of a radous detection performance than in minimum detectable signal(Smin). (10M).(b.) What do you understand by the terms duty cycle and unambiguous range of a radar?What is the technique employed for resolving range ambiguifier. (10M).

3(a.) draw the block diagram of a pulsed RADAR and explain the significance of designing IF amplifier as a matched filter.List the properties of a matched filter for RADAR application. (10M).(b.) Explain the need for integration of RADAR pulses and define the following terms:(10M)(i) Integration Efficiency(IE).(ii)Integration Improvement Factor(IIF)(iii)Integration Loss(IL)

4(a.) Describe the type of operation of a line type radar modulator.What are the advantages of that type of modulator?What is its most significant drawback? (10M)(b.) What are the basic differences between a search radar and a tracking radar? Discuss the various scanning techniques and tracking mechanisms.(10M).

5(a.) What are the advantages of using pulse compression techniques in radar system? Explain the principle of phase coded pulse compression technique with proper diagrams and the advantage gained. (10M)(b.)State the factors which influence the bandwidth of radar receiver.Write down the advantages of large bandwidth. (10M).

6(a.) Explain how the problem of blind speed can be overcome by use of multiple PRF in this radar. Explain how multiple staggered PRF’s can be processed with a transversal(non recursive) filter. (10M)(b.) Explain the role of loop antennas in radio direction binders.What is the need for a sense binder antenna system.Enumerate various methods employed for increasing loop voltage. (10M).

N.B.: (1) Question no.1 is compulsory. [ Total Marks:100] (2.) Attempt any four questions out of remaining six questions.

1 (a.) Explain Radar resolution in brief. (5M) (b.) What is Hyperbolic Navigation? (5M) (c.) Explain remote sensing radar in brief. (5M) (d.) What do you understand by the term four point tracking? (5M).

2.(a.) Derive the Radar range equation as governed by minimum detectable signal to noise ratio.Enumerate the system losses that might occur in a long range surveillance radar and indicate the typical value of the losses due to each factor. (10M).(b.) Describe the chief characteristics of the radar echo from a target when its radar cross-section is in the (i) Rayleigh region (ii) Resonance region and(iii) In the optical region. (10M).

3.(a.) What do you understand by the term clutter? Explain the different types of clutter.Enumerate the properties of Sea and Land clutter. (10M).(b.) What is the drawback in simple CW Radar? How it is overcome in CW- IF Radar?Draw and explain CW- IF Radar in detail. (10M).

4(a.) Draw the functional block diagram of an MTI radar system and explain its operation. Define the terms range tracking and MTI improvement factor. (10M).(b.) What do you mean by blind speed? Explain in detail how this problem is overcome in pulse doppler Radar. (10M).

5(a.)What do you mean by RCS fluctuations? Explain different swerlings model for RCS fluctuations. (10M)(b.) Explain the principle of operation of Loran A and Loran C. (10M).

6(a.)With a suitable block diagram explain the working of a conical scan tracking radar. Explain the various factors that need to be considered in determining the optimum squint angle. (10M).(b.) What is the purpose of Instrument Landing System (ILS)? Explain the limitations of ILS and how the same have been overcome in the MLS. (10M).

JUNE 2007 QUESTION PAPER N.B.:(1) Question no.1 is compulsory. [Total Marks:100] (2.) Attempt any four questions out of remaining six questions. (3.) Figures to the right indicate full marks.

1(a.) Explain remote sensing radar in brief. (5M) (b.) What do you understand by the term four point tracking? (5M) (c.) Explain in brief the various system losses in the radar. (5M) (d.) Explain in brief radar resolution cell. (5M)

2(a.) Describe the chief characteristics of the radar echo from a target when its radar cross-section is in the (i) Rayleigh region (ii) Resonance region and(iii) In the optical region. (10M).(b.) Explain the methods for the integration of radar pulses to improve detection. Define the term integration improvement factor. How does this factor affect the radar range equation? (10M)

3(a.) What do you mean by RCS fluctuations? Explain different swerlings model for RCS fluctuations. (10M)(b.) What is the drawback in simple CW Radar? How it is overcome in CW- IF Radar?Draw and explain CW- IF Radar in detail. (10M).

4(a.) Explain the function of single delay line canceller and derive an expression for the frequency response function. How the drawback of clutter attenuation problem is overcome by double line canceller? (10M)(b.) Draw the functional block diagram of an MTI radar system and explain its operation. Define the terms blind speed and MTI improvement factor. (10M).

5(a.) With a suitable block diagram explain the working of a conical scan tracking radar. Explain the various factors that need to be considered in determining the optimum squint angle. (10M).(b.) State the factors which influence the bandwidth of radar receiver.Write down the advantages of large B.W. . (10M)

6(a.)Explain the limitations of ILS and how the same have been overcome in the MLS? (10M)(b.) Explain the principle of operation of Hyperbolic Navigation system. Compare the principle of operation of Loran A and Loran C. (10M).

N.B.:(1) Question no.1 is compulsory. [ Total Marks:100] (2.) Attempt any four questions out of remaining six questions. (3.) Figures to the right indicate full marks.1(a.) Explain in brief the various system losses in the radar. (5M) (b.) What do you understand by the term Radar resolution cell? (5M) (c.) Explain Instrument Landing system in brief. (5M). (d.) Explain DECCA. (5M).

2(a.) Derive the Radar range equation in terms of Noise figure. (10M). (b.) (i.) The receiver of a radar has noise figure of 6 dB. If the IF- bandwidth B of the receiver is 3MHz, calculate the minimum detectable power. (5M). (ii) If the radar is designed for operation at 10GHz with an antenna of diameter 2m. , calculate the peak pulse power required to have a maximum range of 1000 km. with a target of cross-sectional area 20m^2. (5M).

3(a.) What do you mean by RCS? Explain the RCS of following: (i.) Sphere (ii) Rod (iii) Complex target (10M) (b.) What do you mean by RCS fluctuations? Explain different swerlings model for RCS fluctuations. (10M)

4(a.) Draw the functional block diagram of an MTI radar system and explain its operation. Define the terms blind speed and MTI improvement factor. (10M) (b.) Derive an expression for doppler frequency shift in terms of transmitted frequency and radial component of target velocity vector. (10M).

5(a.)(i.) An MTI Radar is operating at 10 GHz with an PRF of 1000Hz.Calculate the lowest three blend speed. (5M). (ii.) The MTI Radar is used by a traffic control police to measure the speed of cars. If the doppler frequency shift measured from the moving car is 1.6 KHz , calculate the speed of the car. (5M).(b.) What do you understand by the term clutter? Enumerate the properties of Sea and Land clutter. (10M).

6(a.) With a suitable block diagram explain the working of a conical scan tracking radar. (10M)(b.) Describe briefly the two different types of phased-array radar.State their functions. (10M).